Protective cage for trench workers

ABSTRACT

A protective cage for trench workers having a plurality of inverted U-shaped frame members supporting a mesh covering. The cage is open at the bottom and ends and the U-shaped frame members are connected together by a top longitudinally extending frame member and bottom longitudinally extending frame members. A folding seat is mounted inside of the cage, and holding means is associated with the seat to secure the operator thereon when the cage is moved into or out of a trench. Safety indicating means are operable by the holding means to signal a person on the ground surface the position of the holding means.

United States Patent [191 Gibson 1 June 25, 1974 PROTECTIVE CAGE FOR TRENCH WORKERS [76] Inventor: Van A. Gibson, 6510 SE. Jack Rd.,

Milwaukie, Oreg. 97222 22 Filed: Jan. 4, 1973 [21] Appl. No.: 320,916

152] US. Cl. 61/41 A, 61/63 [51] lnt.Cl E2ld 5/00,E21d 5/12 [58] Field of Search; 61/41 A, 41, 63, 84, 45 R [56] References Cited UNITED STATES PATENTS 2,633,713 4/1953 Shields 61/41 A 2,777,294 1/1957 Rosa et a1. 61/41 A X 2,866,320 12/1958 Bazzell A 3,204,415 9/1965 Hill et al. 61/41 A FORElGN PATENTS OR APPLICATIONS 1,383,953 11/1964 France 61/41 A 532,849 1/1941 Great Britain 61/41 A Primagy Examiner--Dennis L. Taylor Attorney, Agent, or Firm-Eugene M. Eckelman 5 7 1 ABSTRACT A protective cage for trench workers having a plurality of inverted U-shaped frame members supporting a mesh covering. The cage is open at the bottom and ends and the U-shaped frame members are connected together by a top longitudinally extending frame member and bottom longitudinally extending frame members. A folding seat is mounted inside of the cage, and holding means is associated with the seat to secure the operator thereon when the cage is moved into or out of a trench. Safety indicating means are operable by the holding means to signal a person on the ground surface the position of the holding means.

3 Claims, 3 Drawing Figures PROTECTIVE CAGE FOR TRENCH WORKERS BACKGROUND OF THE INVENTION I This invention relates to new and useful improvements in protective devices for trench workers and the like.

Trench shoring means have heretofore been provided for protecting workmen in trenches against caveins and the like. In some cases, shoring structure is constructed within the trench and then removed when there is no longer need for it. Apparatuses have also been provided for use in a trench and capable of being moved along the trench as the work progresses. The first form of protective means of course consumes considerable time in construction as well as in its removal. Such structure adds considerable expense to the project. The second means, utilizing the machines which are movable along the trench, are extremely bulky and expensive to manufacture, and furthermore such prior devices have not been capable of being handled by machinery usually present on the small or medium size projects.

SUMMARY OF THE INVENTION According to the present invention and forming a primary objective thereof, a protective cage is provided for trench workers having a novel construction facilitating efficient usage and at the same time being arranged to be handled by lifting devices, such as back hoes, found on substantially all size projects. The structure of the present cage is also simplified so that the average contractor can well afford to purchase and use one.

More particular objects of the present invention are to provide a protective cage of the type described employing a plurality of inverted U-shaped frame portions secured together at the top and bottom and covered around the top and sides by a protective mesh covering; to provide seat means in said cage for supporting a workman so that he can ride with the cage into and out of the trench, and furthermore to provide releasable operator holding means for the workman on the seat which includes an automatically operating signal visible from above to indicate to persons on the ground surface the position of the operator holding means.

The invention will be better understood and additional objects and advantages will become apparent from the following description taken in connection with the accompanying drawings which illustrate a preferred form of the device.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view of a protective cage DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT Referring specifically to the drawings, the protective cage of the present invention comprises a plurality of upright parallel frame portions 10. These frame portions are of inverted U-shaped construction, having a pair of posts or legs 10a and connecting tops 10b. They are secured integrally together by a top longitudinal frame member 12 and bottom longitudinal frame members 14. As illustrated, the frame member 12 may comprise an I-beam, and the bottom frame members 14 may comprise channels in which the bottoms of the posts 10a seat and are secured. Preferably, the tops 10b of the frame portions 10 are rounded.

A covering 16 of a structurally strong mesh material is secured on the sides and over the top of the frame portions 10. Expanded metal is preferred for the covering 16 since it is structurally strong, light in weight, and provides adequate protection. Such material also provides good ventilation. Securement of the covering 16 to the frame portions may be accomplished by welding or the like and serves to strengthen the over-all structure. The bottom of the cage is open. The ends are also open except for one or more transverse reinforcing members 18 in such ends.

The top longitudinal frame member 12 has an eye or other suitable connecting member 20 to receive a hook or the like on a line from a powered lifting machine so that the cage can be moved into and out of a trench and along a trench. The eye 20 is centered between the ends so that the cage will be substantially stable when lifted. The cage although being sufficiently large to allow a workman to work therein, is sufficiently small and of light weight to permit average equipment to handle it for movement into and out of a trench and along a trench.

A seat 24 is mounted inside of the cage for supporting a workman when the cage is being handled by the lifting apparatus. This seat comprises a bottom or seat portion 26 and a back portion 28. The back portion 28 has a hinge connection 29 with the seat portion 26 so that it can be folded flat down on the seat portion. The seat portion 26 is supported at its ends on longitudinally extending supports 30 secured as by welding between two of the upright posts 10a. One end of the seat portion 26 has a hinge connection 32 with one of the supports 30, and with this hinge connection as well as the hinge connection 29 between the seat portions 26 and 28, the portion 28 can be folded flat and then the entire seat folded upwardly to a vertical out-of-the-way position. FIG. 3 shows in phantom lines the folded position of the back 28 on the seat 26 and also the folded position of both the back and seat to its vertical position. A hinged latch member 36 on the post 10a is arranged to releasably hold the seat in its upright position between such latch member and the covering 16.

Means to hold the operator on the seat, such as a chain or belt 40, is associated with the seat. One end of this holding means is releasably attachable to an anchor 42 at one side of the seat. The other end of the holding means 40 is secured permanently to the bottom end of an upright rod 44 slidably disposed in upper and lower guides 46 secured on one of the frame members 10. The upper end of the rod 44 projects through the covering l6 and comprises an indicating end terminating at the top in an enlargement 48. The rod 44 is freely slidable in the guides 46 and normally tends to fall by gravity to a lowered position wherein the enlargement 48 seats on guide 46.

The lowered position of the rod 44 comprises a position wherein the holding means 40 is not in use. In this position, the holding means 40 hangs loose, FIG. 1. The holding means 40 is of a selected length whereby it cannot be fastened across the operator to anchor 42 without lifting the rod 44. To secure himself in place on the seat, the workman must therefore raise the rod to its upper position. This brings the lower end of the rod up to the plane of his lap and he can then attach the free end of the holding means 40 to the anchor 42. Since the rod 44 is disposed in its upper position when the workman is secured in place on the seat, the operator of the lifting device on the ground in viewing the upper end of the rod 44, can be assured that the workman in the cage has secured himself on the seat. There is thus no chance of a workman being injured by premature lifting or moving of the cage.

in the use of the present cage, a portion or all of a trench may first be dug and then the work in the trench, such as pipe laying be accomplished. To get the workman and cage into the trench, the workman steps into the cage while the latter is still above ground and secures himself in place on the seat 24 by holding means 40. The cage is then lowered into the trench by the lifting device, and upon reaching the bottom of the trench the workman releases the holding means 40 and raises the seat to its latched, out-of-the-way position. As the workman progresses along the trench, the cage is moved therealong by the lifting device. The workman may either secure himself on the seat each time the cage is moved along the trench or if he can safely do it he may merely stand on the bottom longitudinal frame members 14 in straddling relation during movement. When the cage is to be lifted out of the trench, the workman again secures himself in place on the seat. If the operator of the lifting device cannot see the workman inside of the cage to make sure he is secured to the seat, he can merely view the rod 44 to see if the workman has strapped himself in.

It may be desirable to use two of the present cages in the laying of pipe or other work in a trench. When using two cages, one cage can be shifted into a new position while the workman is working in the other. This way, there is no slack time.

It is to be understood that the form of my invention herein shown and described is to be taken as a preferred example of the same and that various changes in the shape, size and arrangement of parts may be resorted to without departing from the spirit of my invention, or the scope of the subjoined claims.

Having thus described my invention, 1 claim:

1. A protective cage for trench workers comprising a. a plurality of upstanding parallel frame portions of inverted U-shape having side posts and a connecting top between the posts,

b. a longitudinal rigid frame member securedv along the tops of said U-shaped frame portions,

c. longitudinal frame members secured along the bottom of said posts,

d. a mesh covering secured around the sides and top of said cage, the bottom of the cage being open,

e. a lift connection on the upper end of said frame for moving said cage into and out of a trench as well as along the trench by a lifting device.

f. a seat mounted interiorly of said cage adapted to support a workman thereon when the cage is being moved into and out of a trench or along a trench, and

g. releasable holding means associated with said seat arranged to hold a workman on the seat.

2. The protective cage of claim 1 wherein said seat is foldable to an out of the way position when not in use.

3. The protective cage of claim 1 including indicating means operated by said holding means in an arrangement whereby said indicating means signals to a workman on the ground surface the operative position of said holding means. 

1. A protective cage for trench workers comprising a. a plurality of upstanding parallel frame portions of inverted U-shape having side posts and a connecting top between the posts, b. a longitudinal rigid frame member secured along the tops of said U-shaped frame portions, c. longitudinal frame members secured along the bottom of said posts, d. a mesh covering secured around the sides and top of said cage, the bottom of the cage being open, e. a lift connection on the upper end of said frame for moving said cage into and out of a trench as well as along the trench by a lifting device. f. a seat mounted interiorly of said cage adapted to support a workman thereon when the cage is being moved into and out of a trench or along a trench, and g. releasable holding means associated with said seat arranged to hold a workman on the seat.
 2. The protective cage of claim 1 wherein said seat is foldable to an out of the way position when not in use.
 3. The protective cage of claim 1 including indicating means operated by said holding means in an arrangement whereby said indicating means signals to a workman on the ground surface the operative position of said holding means. 